Field
The present disclosure generally relates to stent-grafts for treating diseases of the vasculature.
Discussion of the Related Art
Stent-grafts are medical devices constructed to reinforce, replace, or bridge, a part of a damaged, unhealthy, or diseased blood vessel. A stent-graft may thus guide blood flow through a lumen defined by its cylindrical interior. Where a stent-graft is implanted in a patient's body, however, blood is typically not permitted to leak or flow over an exterior portion of the stent-graft.
Occasionally, a stent-graft may be placed in a part of a patient's body such that it occludes or blocks one or more side-branch vessels (i.e., vessels that join the main vessel within which the stent-graft is implanted). For instance, patients who develop abdominal aortic aneurysms (“AAAs”) are often implanted with stent-grafts. During a procedure of this type, a stent-graft may be implanted in a patient's abdominal aorta. However, such a stent-graft may partially or fully occlude blood flow to a patient's renal arteries, which branch away from the patient's abdominal aorta.
Commonly, in order to direct blood flow to a patient's side-branch vessels, stent-grafts, which may otherwise occlude these vessels, are manufactured with, or altered in situ to include, a fenestration or window near a location of one or more side-branch vessels. Thus, in operation, blood may escape through the fenestration and into one or more side-branch vessels.
Fenestrated stent-grafts have been manufactured with their fenestrations opened a priori of surgical implantation. More particularly, fenestrated stent-grafts have been manufactured as pre-sized commercial off the shelf components as well as more customized components fenestrated based upon preoperative anatomic information (e.g., imaging data collected via x-ray systems, etc.) In either instance, however, a fenestrated stent-graft may fit poorly within a patient's anatomy (either due to the pre-sized nature of the device and/or as a result of inadequate or imprecise preoperative anatomic data). Likewise, where stent-grafts have been fenestrated in situ, it has been similarly challenging to adjust the orientation of such stent-grafts to align with various anatomies.
In light of these shortcomings, physicians have struggled to ensure alignment between the fenestrations made in stent-grafts and the branch-vessels into which these fenestrations will ultimately direct blood flow. For example, until now, alignment has been accomplished (and/or attempted) largely through the use of multiple guidewires as well as, in some instances, an angiographic catheter. These measures have been necessary, because stent-grafts, as described above, may fit only poorly into their respective anatomies. Moreover, where stent-grafts have been implanted near side-branch vessels, physicians have struggled, prior to alignment of one or more fenestrations with these vessels, with occlusion by the stent-graft of these vessels.
A more suitable fenestrated stent-graft is therefore desirable. More particularly, a stent graft suited to more careful placement in a patient's anatomy is desirable. A need similarly exists for the reduction of surgical equipment in a patient's anatomy. Likewise, there is a need for a stent-graft that does not occlude side-branch vessels prior to alignment.